<!DOCTYPE html>
<meta charset="UTF-8">
<title>CSS Highlight API Test: </title>
<head>
  <style>
    div {
      margin: 40px;
      font-size: 20px;
    }
    #h1 {
      text-underline-offset: 10px;
      text-decoration-line: underline;
      text-decoration-color: green;
      text-decoration-thickness: 4px;
    }
    #h2 {
      text-underline-offset: 20px;
      text-decoration-line: underline;
      text-decoration-color: blue;
      text-decoration-thickness: 2px;
    }
  </style>
</head>
<body>
  <div id="h1">A green 10px offset underline 4px thick</div>
  <div id="h2">A blue 20px offset underline 2px thick</div>
</body>